In recent years, there has been a strong demand for inexpensive zoom lens shutter cameras which have good portability (i.e., are small and light weight), which in turn requires the zoom lenses installed in the cameras be small, inexpensive, and of high performance. Examples of relatively inexpensive zoom lenses with simple structures having three lens elements are disclosed in Japanese Laid-Open Patent Publication 3-127013, Japanese Laid-Open Patent Publication 3-158815 and Japanese Laid-Open Patent Publication 7-294815.
However, zoom lenses of the aforementioned Japanese laid-open patent publications use expensive, aspherical molded-glass lens elements, are too large due to a long distance between each lens element in the front lens group, or the ease of production is not good, even when inexpensive plastic lenses are used, due to the use of many aspherical surfaces. Thus the prior art zoom lenses often fail to meet the market demand.
In the zoom lenses of the aforementioned Japanese laid-open patent publications, a negative lens element is arranged on the object-side of the front lens group. However, the refractive power of each zoom lens is made small by having the distance between the negative lens element and the positive lens element be large, or the aberration corrections are made easier by arranging a stop behind the positive lens element. In either case, the zoom lens fails to satisfy the market demand for a compact system, since the zoom lens becomes longer or the diameter of the front lens element of the zoom lens becomes larger than is necessary.